Transport Coefficients in non equilibrium argon-hydrogen thermal plasmas

Vincent Rat (1) , Jacques Aubreton (1) , Pascal André (2) , Marie-Françoise Elchinger (1) , Pierre Fauchais (1) , André Lefort (2)

1 Axe 2 : procédés de traitements de surface
2 LAEPT - Laboratoire arc électrique et plasmas thermiques

Transport coefficients in non-equmbrium argon-hydrogen thermal plasmas, where the kinetic temperature of electrons Te is different from that of heavy species Th, are calculated at atmospheric pressure from a recent theoretical approach of Rat et al. The latter consists in deriving transport properties in thermal plasmas from the solution of the Boltzmann's equation according to the Chapmann Enskog method keeping the coupling between electrons and heavy species. Plasma composition is obtained from a non equilibrium constant method and a stationnary kinetic calculation. First, electrical and translational thermal conductivities are compared with those evaluated with the simplified theory of transport properties of Devoto and Bonnefoi. Non-neglible discrepancies occur reaching more than 30% and 40% respectively for the electrical and electron thermal conductivities at Te= 15000 K for theta = 2. Second, the dependence with Te of electrical and total thermal conductivities (including translational, internal and reactional contributions) and viscosity is examined as a function of the method of calculation of plasma composition and the non-equilibrium parameter theta= Te /Th . It is emphasized that non-equilibrium transport coefficients are strongly dependent on the method of plasma composition.

Mots clés: Transport Coefficients; Argon-Hydrogen; two-temperature; thermal plasma

Domaines: Physique des plasmas [physics.plasm-ph]

Vincent Rat, Jacques Aubreton, Pascal André, Marie-Françoise Elchinger, Pierre Fauchais, et al.. Transport Coefficients in non equilibrium argon-hydrogen thermal plasmas. 7th European Conference on Thermal Plasma Processes, 2003, France. pp.269-274. ⟨hal-00019939⟩